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<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
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</head>
<body>
    <input type="button" id="hide" value="隐藏"></input>
    <input type="button" id="show" value="显示"></input>
    <ul id="ul_id">
        <li>Pyython</li>
        <li>Java</li>
    </ul>
    <script type="text/javascript">

        $button_hide = $('#hide');
        $button_show = $('#show');

        $ul = $('#ul_id');
        $button_hide.click(function () {
            $ul.hide("slow")
        })
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            $ul.show("fast")
        })
    </script>
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